<template>
	<el-breadcrumb class="app-breadcrumb" separator="/">
		<transition-group name="breadcrumb">
			<el-breadcrumb-item v-for="(item, index) in levelList" :key="item.path">
				<span v-if="item.redirect === 'noRedirect' || index == levelList.length - 1" class="no-redirect">{{ item.meta.title }}</span>
				<a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
			</el-breadcrumb-item>
		</transition-group>
	</el-breadcrumb>
</template>

<script setup>
import usePermissionStore from '@/store/modules/permission'

const route = useRoute()
const router = useRouter()
const permissionStore = usePermissionStore()
const levelList = ref([])

function getBreadcrumb() {
	// only show routes with meta.title
	let matched = []
	const pathNum = findPathNum(route.path)
	// multi-level menu
	if (pathNum > 2) {
		const reg = /\/\w+/gi
		const pathList = route.path.match(reg).map((item, index) => {
			if (index !== 0) item = item.slice(1)
			return item
		})
		getMatched(pathList, permissionStore.sidebarRouters, matched)
	} else {
		matched = route.matched.filter((item) => item.meta && item.meta.title)
	}
	// 判断是否为首页
	if (!isDashboard(matched[0])) {
		matched = [{path: '/index', meta: {title: '首页'}}].concat(matched)
	}
	levelList.value = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false)
}

function findPathNum(str, char = '/') {
	let index = str.indexOf(char)
	let num = 0
	while (index !== -1) {
		num++
		index = str.indexOf(char, index + 1)
	}
	return num
}

function getMatched(pathList, routeList, matched) {
	let data = routeList.find((item) => item.path == pathList[0])
	matched.push(data)
	if (data.children && pathList.length) {
		pathList.shift()
		getMatched(pathList, data.children, matched)
	}
}

function isDashboard(route) {
	const name = route && route.name
	if (!name) {
		return false
	}
	return name.trim() === 'Index'
}

function handleLink(item) {
	const {redirect, path} = item
	if (redirect) {
		router.push(redirect)
		return
	}
	router.push(path)
}

watchEffect(() => {
	// if you go to the redirect page, do not update the breadcrumbs
	if (route.path.startsWith('/redirect/')) {
		return
	}
	getBreadcrumb()
})
getBreadcrumb()
</script>

<style lang='scss' scoped>
.app-breadcrumb.el-breadcrumb {
	display: inline-block;
	font-size: 14px;
	line-height: 50px;
	margin-left: 8px;

	.no-redirect {
		color: #97a8be;
		cursor: text;
	}
}
</style>
